Hypertension is a major risk factor that contributes to more than 625,000 fatal heart attacks and strokes each year in this country alone. Left untreated, high blood pressure can also lead to kidney and heart failure. With nearly 76 million baby boomers now approaching mid-life and beyond the numbers will continue to rise. It is well known that high blood pressure increases the risk of heart disease and stroke, which are the first and third leading causes of death for Americans. Based on National Health and Nutrition Examination Survey III [NHANES III, 1988-91], Centers for Disease Control and Prevention/National Center for Health Statistics about 50 million Americans aged 60 and older have high blood pressure (or hypertension). In fact, one in five Americans (and one in four adults) has high blood pressure and 31.6 percent of hypertensives are undiagnosed. It has been demonstrated that early detection and intervention results in dramatic reductions in mortality and morbidity in hypertensive subjects.
The NIH describes congestive heart failure as the “new epidemic.” Over 4.8 million individuals in the USA are diagnosed with congestive heart failure, with 400,000-700,000 new cases reported each year. Within the next 5 years, 20 million Americans will discover symptoms that are early warning signs for impending congestive heart failure including increased blood pressure. An estimated 10 million persons have diabetes in USA. Diabetes puts patients at a high blood pressure, heart disease, circulatory problems, and vision problems. In diabetics, blood pressure control can help reduce long-term complications. Thus, there are many groups that can benefit from the use of passive, on-demand blood pressure measurements.
Most doctors will diagnose a person with high blood pressure on the basis of two or more pressure readings taken from the brachial artery over several office visits. For patients with disparate readings, home monitoring is the method of choice and is now reimbursed by health maintenance organizations (HMOs). Home monitoring of blood pressure has certain advantages; it will avoid what is sometimes termed “white-coat hypertension” or elevated pressures due to nervousness in a doctor's office, and home monitoring of blood pressure will provide more accurate temporal measurements. Blood pressure can be measured using a variety of methods including mercury sphygmomanometer (the current gold standard), electronic blood pressure monitors, and by calculating blood pressure from mathematical transformations of pulse waves. For continuous blood pressure measurements, an ambulatory blood pressure monitoring device is employed. This device is usually worn for 24 hours and can take blood pressure at pre-programmed intervals (usually every 30 minutes). An ambulatory blood pressure device must be worn on the arm throughout the entire diagnostic period, which can be an inconvenience. Conventional blood pressure monitors have other disadvantages in that they are bulky, may cause hazardous mercury spills, and may be difficult to use by elder adults or the cognitively impaired. Furthermore, there is low patient compliance with taking blood pressure measurements regularly at home, due to the aforementioned disadvantages and/ or inconveniences.
The ability to measure blood pressure and other vital signs, such pulse rate; weight; and body mass index (BMI), and percent body fat during the time it takes for a typical morning weight check, and then automatically store the information in a database for continuous analysis could have a beneficial effect on the early detection of disease.